Animals and experimental design
The experiment was conducted in the poultry section of the Iguatemi Experimental Farm, State University of Maringá, under the approval of the Animal Experimentation Ethics Committee (Comitê de É tica de Animais em Experimentação/Universidade Estadual de Maringá-CEEA/UEM-Registration No. 034/2011). The study included 952 Cobb male broiler chicks, distributed into a completely randomised experimental design of four treatments (diets containing different vitamin D3 metabolites), seven replicates and 34 birds per experimental unit.